In general, you should always discuss licensing questions with your ServiceNow account team as they are the best to answer as they know your contract details and any possible exceptions.
However, typically a user with no entitlements assigned can only view the requests they submit and some general metadata like knowledge articles. This generally applies to IT Service Management. So for most ITSM data, a user with no licensed entitlement couldn't see much on any dashboard or report. A user with an ITSM entitlement is typically called a fulfiller can can see all that data in reports or dashboards. ServiceNow does offer a Business Stakeholder role. Users with the Business Stakeholder role can view all ITSM data, so they could run reports and view dashboards.
So to answer your question, the short answer is no. But with the Business Stakeholder of a fun ITSM fulfiller subscription, they could view dashboards and reports.
